build system and module refactoring + simple histogram scratch (#20)

* scratch adding histogram to image views

Histograms should come from some sort of histogram service. This is
currently just a POC.

* custom logger implementation w/o spdlog

* missing cmake file

* fix tests

* use operator<< over direct stream exposure

* rm print header

* add threading test + refactor towards interface libraries

omits the need for =target_include_directories= calls /everywhere/

* rm print header

* rm constexpr

* templated thread_pool

* fix doxyfile

* default enable doc building

* czi reader refactor

* rm erroneous include expression

* clang-format

* single lib include with PUBLIC visibility

* compile imgui stdlib

* clang format

* documentation update

centralize `LogLevelToString` to `ILog.hpp`

update docs and examples

examples/simple/CMakeLists.txt

@@ -6,16 +6,5 @@ set(SIMPLE_NAME "${PROJECT_NAME}_SIMPLE")
 add_executable(${SIMPLE_NAME} ${SRC})
 
 target_link_libraries(${SIMPLE_NAME}
-  PRIVATE pixelariumimagelib
-  PRIVATE pixelariumutilslib
-  PRIVATE pixelariumresourcelib
   PRIVATE pixelariumapplicationlib)
 
-target_include_directories(${SIMPLE_NAME}
-  PRIVATE ${PROJECT_SOURCE_DIR}/src
-  PRIVATE ${PROJECT_SOURCE_DIR}/lib
-  PRIVATE ${PROJECT_SOURCE_DIR}/lib/imaging
-  PRIVATE ${PROJECT_SOURCE_DIR}/lib/app
-  PRIVATE ${spdlog_DIR}/include
-  PRIVATE ${LIBCZI_INCLUDE_DIR}
-  PRIVATE ${CMAKE_CURRENT_BINARY_DIR})