Resolve "Various issues with dependency scripts"

This MR adds some tests for the scripts based on bats-core, and enables its automatic execution by the CI.

It also changes the separator for dependency flavors from : to % to prevent clashing with the version separator for profiles (e.g. libfabric:experimental@mogon2:latest was ambiguous to bash).

Two new bash functions determine_compiler() and profile_has_dependency() are added to compile_dep.sh that are made available to install scripts:

• The determine_compiler() function makes its best to determine the default compiler available in the system. Installation scripts can access this information via the COMPILER_NAME, COMPILER_FULL_VERSION, and COMPILER_MAJOR_VERSION variables.
• The profile_has_dependency() function allows installation scripts to check whether another dependency is provided by the currently loaded profile, and act accordingly. The function accepts a bash regex with the search argument.

Additionally, this MR fixes the following problems in dl_dep.sh and compile_dep.sh:

• Using -d option in dl_dep.sh ends up downloading all dependencies (#176 (closed))
• Specifying a full profile in dl_dep.sh with -d does not work (#177 (closed))
• dl_deps.sh can download the same dependency in several versions but unpacks them into the same directory (#178 (closed))
• libfabric experimental not working (#180 (closed))
• psm2 is viewed as a dependency when in fact it is build as part of libfabric. Therefore if [[ "$((${#wgetdeps[@]}+${#clonedeps[@]}))" -ne "${#order[@]}" ]]; then fails (#180 (closed))
• rocksdb experimental not working (#180 (closed))
• rocksdb install of newer versions needs PREFIX for make install to specify install path (#180 (closed)) (Moving to CMake for 0.9.0
• When clonedeps is using a tag/branchname to clone, e.g., HEAD@v1.12.1, clonedeps_args for the dependency needs explicit space, e.g., ["mercury"]=" --recurse-submodules" otherwise the script fails.
• Dependency patches are being skipped (#184 (closed)).
• Script should use script directory as pwd instead of bash_pwd?

Closes #176 (closed) #177 (closed) #178 (closed) #180 (closed) #184 (closed)