Merge branch 'web-opt-images' into 'master'

web/content/books/BMB-2-Cover.png

web/content/books/BMB-3-Cover.png

web/content/books/Computation-Hydrology-I-Cover.png

web/content/books/bmb-4.png

web/content/books/computational-geotechnics-i.png

web/content/books/computational-hydrology-ii.png

web/content/books/geoenergy-modeling-i.png

web/content/books/geoenergy-modeling-ii.png

web/content/books/geoenergy-modeling-iii.png

web/content/books/models-of-thermochemical-heat-storage.png

...content/docs/benchmarks/creep-after-excavation-bgra/T.png

...tent/docs/benchmarks/creep-after-excavation-bgra/mesh.png

...nt/docs/benchmarks/creep-after-excavation-bgra/strain.png

...nchmarks/creep-after-excavation-bgra/stress_xx_yy_110.png

...enchmarks/creep-after-excavation-bgra/stress_xx_yy_20.png

...enchmarks/creep-after-excavation-bgra/stress_xx_yy_50.png

web/content/docs/benchmarks/creepbgra/bgra0.png

...6_gwf_with_nodal_source_term_analytical_solution_head.png

..._with_nodal_source_term_diff_analytical_solution_head.png

...l_source_term_diff_analytical_solution_head_log_scale.png