Tune the makefile according to new principles, which adds a few bells
and whistles and for clarity.
Synopsis:
* The dependency on opm-common is completely gone. This is reflected in
travis and appveyor as well. No non-kitware cmake modules are used.
* Directories are flattened, quite a bit - source code is located in the
lib/ directory if it belongs to opm-parser, and external/ if third
party.
* The sibling build feature is implemented through cmake's
export(PACKAGE) rather than implicitly looking through source files.
* Targets explicitly set required public and private include
directories, compile options and definitions, which cmake will handle
and propagate
* opm-parser-config.cmake for downstream users is now provided.
* Dependencies are set up using targets. In the future, when cmake 3.x+
can be used, these should be either targets from newer Find modules,
or interface libraries.
* Fewer system specific assumptions are coded in, instead we assume
cmake or users set up system specific details.
* All module wide configuration and looking up libraries is handled in
the root makefile - all sub directories only set up libraries and
compile options for the module in question.
* Targets are defined and links handled transitively because cmake now
is told about them. ${module_LIBRARIES} variables are gone.
This is largely guided by the principles outlined in
https://rix0r.nl/blog/2015/08/13/cmake-guide/
Most source files are just moved - if they have some content change then
it's nothing more than include fixes or similar in order to make them
compile.
Replaces the internal inheritance + unique_ptr scheme to a flat sum type
similar scheme that uses a tag to determine which operations are legal,
rather than using the indirection itself as a tag.
just like for macros that start and end with `__`, `clang++
-Weverything` likes to complain about macros which start and end with
a single underscore. This is basically the same issue as
Ensembles/ert#1048
- use a opm-macro to reduce code duplication
- add a 'test-suite' target which builds tests. for use if BUILD_TESTING
is 0.
- add a 'check' target which builds tests, then executes them
this is just the result of
```
find -iname "*.[ch]pp" | xargs sed -i "s/ *$//"
find opm/parser/share/keywords -type f | xargs sed -i "s/ *$//"
```
so if it causes conflicts with other patches, the others should get
priority. The rationale behind this patch is that some people tell
their editor to remove white space which leads to larger than
necessary patches...
The class Value<T> will keep track of a named variable, and whether that
particular value has been explicitly initialized. Will throw
std::logic_error if trying to use an unitialized value.
